Morphogenetic sequences during tadpole tail regeneration

1976 ◽  
Vol 54 (8) ◽  
pp. 1314-1325 ◽  
Author(s):  
Kristine H. Atkinson ◽  
Burr G. Atkinson ◽  
Peter A. Merrifield
Keyword(s):  
Epithelial Cells ◽  
Rana Catesbeiana ◽  
Neuromuscular Junctions ◽  
Muscle Fibers ◽  
Proximal Region ◽  
Chronological Order ◽  
Tail Regeneration ◽  
Nerve Axon ◽  
Early Stages ◽  
Tadpole Tail

The appearance of differentiated tissue types after amputation of Rana catesbeiana tadpole tail follows a precise chronological order. Migrating epithelial cells invest the wound within 3 days. Blastemal cells accumulate under the distal epithelium in the early stages when tissue debris is cleared away, then by day 11 notochordal outgrowth and nerve axon replacement predominate in the highly vascularized blastema.Fusion of the myoblasts to form the first detectable myotubes occurs in the proximal region of the regenerate by day 14. Myogenesis proceeds distally with myotubes present under the epithelium of the distal tip of the regenerate at day 19. After day 22 further increase in tail musculature is probably due to the growth of fibers already formed. At day 22 the new muscle fibers begin to anastomose with the healed ends of the old fibers. From 35 to 48 days the major remaining difference from control tissues is the size and extent of the regenerated muscle fibers; capillaries, axons, epidermis and dermis, and neuromuscular junctions are morphologically indistinguishable from unregenerated tissues.

Gill irrigation in Rana catesbeiana. Part I. On the anatomical basis

1972 ◽  
Vol 50 (5) ◽  
pp. 481-499 ◽  
Author(s):  
Norman Gradwell
Keyword(s):  
Epithelial Cells ◽  
Muscle Fiber ◽  
Rana Catesbeiana ◽  
Muscle Fibers ◽  
Functional Studies ◽  
Anatomical Basis ◽  
Different Types ◽  
The Difference ◽  
Anuran Tadpole ◽  
First Time

The gross and histological anatomy of the gill irrigation apparatus are discussed. Two histologically different types of muscle fiber are identified in certain muscles by virtue of the difference in the proportion of fibrillar to sarcoplasmic material in the muscle fibers. An accessory jaw tendon, the valve of the first gill cleft, and several ligaments are described for the first time in an anuran tadpole. An opercular muscle and a fascia lateralis are also described for the first time in a ranid tadpole. The rugulose lining of the pharynx is well vascularized; attention is also drawn to epithelial cells whose points project into the lumen of the pharynx. Several discrepancies in the literature on tadpole anatomy are discussed. To facilitate functional studies, an alphanumeric terminology is proposed for the branchiomeric muscles.

Proportion of muscles spindles supplied by skeletofusimotor axons (beta-axons) in peroneus brevis muscle of the cat

1975 ◽  
Vol 38 (6) ◽  
pp. 1390-1394 ◽  
Author(s):  
F. Emonet-Denand ◽  
Y. Laporte
Keyword(s):  
Neuromuscular Junctions ◽  
Muscle Fibers ◽  
Repetitive Stimulation ◽  
Motor Axon ◽  
Dynamic Sensitivity ◽  
Conduction Velocities ◽  
Peroneus Brevis ◽  
Stimulation Of

Of 32 cat peroneus brevis spindles, 23 (72%) were found to be supplied by a least 1 skeletofusimotor or beta-axon. A motor axon was identified as skeletofusimotor when repetitive stimulation of it elicited both the contraction of extrafusal muscle fibers and as acceleration of the discharge of primary ending, which persisted after selective block of the neuromuscular junctions of extrafusal muscle fibers. The block was obtained by stimulating single axons at 400-500/s for a few seconds. Of 135 axons supplying extrafusal muscle fibers, 24 (18%) were shown to be beta-axons; 22 beta-axons had conduction velocities ranging from 45 to 75 m/s. All but three beta-axons increased the dynamic sensitivity of primary endings. Beta-innervated spindles may also be supplied by dynamic gamma-axons.

Mechanical properties of the tadpole tail fin

1998 ◽  
Vol 201 (19) ◽  
pp. 2691-2699 ◽  
Author(s):  
PA Doherty ◽  
RJ Wassersug ◽  
JM Lee
Keyword(s):  
Stress Relaxation ◽  
Large Deformation ◽  
Forced Vibration ◽  
Viscoelastic Properties ◽  
Developmental Plasticity ◽  
Rana Catesbeiana ◽  
Small Deformation ◽  
Collagen Fibres ◽  
Tadpole Tail ◽  
Undulatory Swimming

The tadpole tail fin is a simple double layer of skin overlying loose connective tissue. Collagen fibres in the fin are oriented at approximately +/-45 degrees from the long axis of the tail. Three tests were conducted on samples of the dorsal tail fin from 6-10 Rana catesbeiana tadpoles to establish the fin's viscoelastic properties under (1) large-deformation cyclic loading at 1 and 3 Hz, (2) small-deformation forced vibration at 1 and 3 Hz, and (3) stress relaxation under a 0.1 s loading time. The fin was very fragile, failing easily under tensile loads less than 7 g. It was also strikingly viscoelastic, as demonstrated by 72+/-1 % hysteresis loss (at 3 Hz), 16+/-3 % stress remaining after 100 s of stress relaxation and a phase angle of 18+/-1 degrees in forced vibration. As a consequence of its viscoelastic properties, the fin was three times stiffer in small than in large deformation. This may account for the ability of the fin to stay upright during normal undulatory swimming, despite the absence of any skeletal support. Tadpoles in nature are often found with damaged tails. We suggest that the unusually viscoelastic and fragile nature of the fin helps tadpoles escape the grasp of predators. Because the fin deforms viscoelastically and tears easily, tadpoles can escape predators and survive otherwise lethal attacks with only minor lacerations to the fin. Recent studies have shown that certain tadpoles develop taller fins in the presence of predators. This developmental plasticity is consistent with the tail fin acting as a protective but expendable 'wrap' around the core muscle tissue.

Inhibition of Zn2+-induced potentiation of twitch tension by Ni2+ in frog muscle

1986 ◽  
Vol 64 (5) ◽  
pp. 625-630
Author(s):  
Toshiharu Oba ◽  
Ken Hotta
Keyword(s):  
Action Potential ◽  
Inhibitory Action ◽  
Channel Blocker ◽  
Rana Catesbeiana ◽  
Muscle Fibers ◽  
Frog Muscle ◽  
Duration Of Action ◽  
Ringer’S Solution ◽  
Mechanical Threshold ◽  
T Tubules

Effect of Ni2+ on Zn2+-induced potentiation of twitch tension was studied electrophysiologically in the toe muscle fibers of Rana catesbeiana. The major findings of this investigation are as follows. When 2 mM Ni2+ was applied to fibers in a normal Ringer's solution containing 50 μM Zn2+ (Zn2+ solution), the Zn2+-potentiated twitch tension decreased remarkably to about one-third of that before Ni2+ treatment. This concentration of Ni2+ caused a 23% decrease in the duration of action potential which had been prolonged by Zn2+ (6.61–5.09 ms). Ni2+ (2 mM) added to normal Ringer's solution led to increases of about 30 and 42% in twitch tension and in the duration of action potential, respectively. A slight increase in the mechanical threshold was induced by 2 mM Ni2+. The inhibitory action of Ni2+ on the twitch tension in Zn2+ solution was larger than that in the case of tetanus tension. Diltiazem (40 μM), aCa2+ channel blocker, did not inhibit the twitch tension potentiated in Zn2+ solution. These results suggest that the decrease in Zn2+-potentiated twitch tension by Ni2+ may possibly derive from impairment of the propagation of action potential along the T tubules.

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